1. Field of the Invention
The invention relates to terpene-based esters and their use as tackifiers in adhesive compositions and more particularly relates to polymeric resin based adhesive compositions improved by the inclusion of terpene-based esters as tackifier components.
2. Brief Description of the Prior Art
The prior art is replete with descriptions of elastomeric, polymeric resin based adhesive compositions; see for example the descriptions given in the U.S. Pat. Nos. 3,554,940 and 3,792,002.
Likewise, esters of Diels-Alder adducts of terpenes and polyols are well known compounds. For example, U.S. Pat. No. 2,253,681 discloses esters of conjugated terpene-fumaric acid -alcohol Diels-Alder complexes; U.S. Pat. No. 2,491,409 discloses polymerizable compositions obtained by an esterification reaction of a polyhydric alcohol, a polycarboxylic acid and an adduct formed by a terpene with certain other reactants.
We have found that high molecular weight terpene-based esters are useful as polar tackifiers when incorporated into elastomeric, polymeric rubber resin based pressure sensitive adhesive compositions.